"Paris - Do you always need reservations for dinner in Paris or for bistros and less formal places can you just "drop in"?"I always make a reservation for several reasons: you get a prime table 9today I sat by the window not the bathroom), they refer to you by name, they know how much food to order/etc and I think it's basically polite.Bistros are hardly uninhabited or casual these days, some serve the best food going.